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.TH UIO.H 3HEAD "Sep 10, 2004"
.SH NAME
uio.h, uio \- definitions for vector I/O operations
.SH SYNOPSIS
.LP
.nf
#include <\fBsys/uio.h\fR>
.fi

.SH DESCRIPTION
.sp
.LP
The <\fBsys/uio.h\fR> header defines the \fBiovec\fR structure, which includes
the following members:
.sp
.in +2
.nf
void   *iov_base     /* base address of a memory region
                        for input or output */
size_t iov_len       /* size of the memory pointed to by
                        iov_base */
.fi
.in -2

.sp
.LP
The <\fBsys/uio.h\fR> header uses the \fBiovec\fR structure for scatter/gather
I/O.
.sp
.LP
The \fBssize_t\fR and \fBsize_t\fR types are defined as described in
<\fBsys/types.h\fR>.
.SH USAGE
.sp
.LP
The symbol {\fBIOV_MAX\fR} defined in <\fBlimits.h\fR> should always be used to
learn about the limits on the number of scatter/gather elements that can be
processed in one call, instead of assuming a fixed value.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Standard
.TE

.SH SEE ALSO
.sp
.LP
.BR read (2),
.BR write (2),
.BR limits.h (3HEAD),
.BR types.h (3HEAD),
.BR attributes (7),
.BR standards (7)
